Tricks for creating stereo from mono?

[[email protected]]

I've tried phase inversion, adding mild reverb and then using a stereo expansion tool. Both provide some degree of a stereo effect, though with phase inversion if you listen in mono - such as on a mobile phone, the audio disappears.

Are there any hifalutin' tricks to creating a more authentic stereo field from a mono source that's also mono compatible?

Thanks for all input.

[William Sommerwerck]

The principle of running the signal through a phase shifter, then adding and
subtracting the phase-shifted signal from the unmodified signal, was used for
many years. Orban made a device that did this (I have one if you want to buy
it), but you'd think it would be part of any modern signal-processing
software. Because the phase-shifted component is out of phase on the
faux-stereo channels, they are inherently mono-compatible.

Adding synthetic ambience from a well-designed hall synthesizer (AHEM!) can
give a very pleasant sense of space and spread. Though some of the added
ambience will cancel when the channels are summed, the process is not truly
mono-compatible.

[Mike Rivers[_2_]]

On 12/30/2014 7:16 PM, wrote:
> I've tried phase inversion, adding mild reverb and then using a
> stereo expansion tool. Both provide some degree of a stereo effect,
> though with phase inversion if you listen in mono - such as on a
> mobile phone, the audio disappears.

Sow's ear /= Silk purse

The Orban stereo synthesizer did a pretty good job of fooling listeners
in the early days of stereo broadcast. I wonder if there's an app for
that. It works by dividing the source into frequency bands and throwing
them left and right. It's more complex than bass on the left, treble on
the right, and it's 100% mono compatible because it doesn't muck with
the left/right phase.


--
For a good time, visit http://mikeriversaudio.wordpress.com

[Adrian Tuddenham[_2_]]

William Sommerwerck > wrote:

> ...some of the added
> ambience will cancel when the channels are summed, the process is not truly
> mono-compatible.

The loss of some of the extra ambience when the channels are summed to
mono is usually a good thing. -in fact, compete removal of the added
ambience may give the best mono results for some types of material.


--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

[Scott Dorsey]

In article >,
> wrote:
>I've tried phase inversion, adding mild reverb and then using a stereo expansion tool. Both provide some degree of a stereo effect, though with phase inversion if you listen in mono - such as on a mobile phone, the audio disappears.
>
>Are there any hifalutin' tricks to creating a more authentic stereo field from a mono source that's also mono compatible?

Try the Orban stereo synthesizers, which are comb filter devices. They
provide a wide sense of space, which is not always a good thing, but can
be useful when building up a mix from mono tracks, and they collapse down
to mono nicely.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Ron C[_2_]]

On 12/30/2014 3:30 PM, Mike Rivers wrote:
> On 12/30/2014 7:16 PM, wrote:
>> I've tried phase inversion, adding mild reverb and then using a
>> stereo expansion tool. Both provide some degree of a stereo effect,
>> though with phase inversion if you listen in mono - such as on a
>> mobile phone, the audio disappears.
>
> Sow's ear /= Silk purse
>
> The Orban stereo synthesizer did a pretty good job of fooling listeners
> in the early days of stereo broadcast. I wonder if there's an app for
> that. It works by dividing the source into frequency bands and throwing
> them left and right. It's more complex than bass on the left, treble on
> the right, and it's 100% mono compatible because it doesn't muck with
> the left/right phase.
>
>
A bunch of years ago I experimented with impulse functions that
would do just that. One can use Sound Forge's acoustic mirror
to create all sorts of impulse functions. Anyway, as I recall, I made
a long sweep and cut it up with the amplitude modulation function,
then created left and right impulses from that. Twas totally mono
compatible.

Been a long time since I played with this stuff so the details of
exactly what I did are a bit fuzzy.

==
Later...
Ron Capik
--

[Les Cargill[_4_]]

Ron C wrote:
> On 12/30/2014 3:30 PM, Mike Rivers wrote:
>> On 12/30/2014 7:16 PM, wrote:
>>> I've tried phase inversion, adding mild reverb and then using a
>>> stereo expansion tool. Both provide some degree of a stereo effect,
>>> though with phase inversion if you listen in mono - such as on a
>>> mobile phone, the audio disappears.
>>
>> Sow's ear /= Silk purse
>>
>> The Orban stereo synthesizer did a pretty good job of fooling listeners
>> in the early days of stereo broadcast. I wonder if there's an app for
>> that. It works by dividing the source into frequency bands and throwing
>> them left and right. It's more complex than bass on the left, treble on
>> the right, and it's 100% mono compatible because it doesn't muck with
>> the left/right phase.
>>
>>
> A bunch of years ago I experimented with impulse functions that
> would do just that. One can use Sound Forge's acoustic mirror
> to create all sorts of impulse functions. Anyway, as I recall, I made
> a long sweep and cut it up with the amplitude modulation function,
> then created left and right impulses from that. Twas totally mono
> compatible.
>
> Been a long time since I played with this stuff so the details of
> exactly what I did are a bit fuzzy.
>
> ==
> Later...
> Ron Capik


I wrote a program to compute the Hilbert transform* of a mono signal.
Add delay and you get... something.

*a fixed, 90-degree phase shift.

You would not confuse the result with ambiance. It would sum to the 45
degree shifted signal in mono.

--
Les Cargill

[Ron C[_2_]]

On 12/30/2014 9:07 PM, Les Cargill wrote:
> Ron C wrote:
>> On 12/30/2014 3:30 PM, Mike Rivers wrote:
>>> On 12/30/2014 7:16 PM, wrote:
>>>> I've tried phase inversion, adding mild reverb and then using a
>>>> stereo expansion tool. Both provide some degree of a stereo effect,
>>>> though with phase inversion if you listen in mono - such as on a
>>>> mobile phone, the audio disappears.
>>>
>>> Sow's ear /= Silk purse
>>>
>>> The Orban stereo synthesizer did a pretty good job of fooling listeners
>>> in the early days of stereo broadcast. I wonder if there's an app for
>>> that. It works by dividing the source into frequency bands and throwing
>>> them left and right. It's more complex than bass on the left, treble on
>>> the right, and it's 100% mono compatible because it doesn't muck with
>>> the left/right phase.
>>>
>>>
>> A bunch of years ago I experimented with impulse functions that
>> would do just that. One can use Sound Forge's acoustic mirror
>> to create all sorts of impulse functions. Anyway, as I recall, I made
>> a long sweep and cut it up with the amplitude modulation function,
>> then created left and right impulses from that. Twas totally mono
>> compatible.
>>
>> Been a long time since I played with this stuff so the details of
>> exactly what I did are a bit fuzzy.
>>
>> ==
>> Later...
>> Ron Capik
>
>
> I wrote a program to compute the Hilbert transform* of a mono signal.
> Add delay and you get... something.
>
> *a fixed, 90-degree phase shift.
>
> You would not confuse the result with ambiance. It would sum to the 45
> degree shifted signal in mono.
>
OK, I wrote my own program, an extended version of acoustic mirror
that allowed me a bit more source material flexibility. I also played with
the Hilbert transform but didn't find it all that useful for audio (music)
processing. [YMMV]

Anyway, a convolution reverb plugin with the right impulse can produce
useful mono to (pseudo) stereo conversions. [again ...YMMV]

==
Later...
Ron Capik
--

[Les Cargill[_4_]]

Ron C wrote:
> On 12/30/2014 9:07 PM, Les Cargill wrote:
>> Ron C wrote:
>>> On 12/30/2014 3:30 PM, Mike Rivers wrote:
>>>> On 12/30/2014 7:16 PM, wrote:
>>>>> I've tried phase inversion, adding mild reverb and then using a
>>>>> stereo expansion tool. Both provide some degree of a stereo effect,
>>>>> though with phase inversion if you listen in mono - such as on a
>>>>> mobile phone, the audio disappears.
>>>>
>>>> Sow's ear /= Silk purse
>>>>
>>>> The Orban stereo synthesizer did a pretty good job of fooling listeners
>>>> in the early days of stereo broadcast. I wonder if there's an app for
>>>> that. It works by dividing the source into frequency bands and throwing
>>>> them left and right. It's more complex than bass on the left, treble on
>>>> the right, and it's 100% mono compatible because it doesn't muck with
>>>> the left/right phase.
>>>>
>>>>
>>> A bunch of years ago I experimented with impulse functions that
>>> would do just that. One can use Sound Forge's acoustic mirror
>>> to create all sorts of impulse functions. Anyway, as I recall, I made
>>> a long sweep and cut it up with the amplitude modulation function,
>>> then created left and right impulses from that. Twas totally mono
>>> compatible.
>>>
>>> Been a long time since I played with this stuff so the details of
>>> exactly what I did are a bit fuzzy.
>>>
>>> ==
>>> Later...
>>> Ron Capik
>>
>>
>> I wrote a program to compute the Hilbert transform* of a mono signal.
>> Add delay and you get... something.
>>
>> *a fixed, 90-degree phase shift.
>>
>> You would not confuse the result with ambiance. It would sum to the 45
>> degree shifted signal in mono.
>>
> OK, I wrote my own program, an extended version of acoustic mirror


I thought Acoustic Mirror was just a fancy suite of impulses?

Also, Google turned up this:

http://www.theromneymarsh.net/history/mirrors.htm

Wow. :)

> that allowed me a bit more source material flexibility. I also played with
> the Hilbert transform but didn't find it all that useful for audio (music)
> processing. [YMMV]
>

Precisely.

> Anyway, a convolution reverb plugin with the right impulse can produce
> useful mono to (pseudo) stereo conversions. [again ...YMMV]
>

Yep.

> ==
> Later...
> Ron Capik

--
Les Cargill

[Ron C[_2_]]

On 12/30/2014 10:33 PM, Les Cargill wrote:
> Ron C wrote:
>> On 12/30/2014 9:07 PM, Les Cargill wrote:
>>> Ron C wrote:
>>>> On 12/30/2014 3:30 PM, Mike Rivers wrote:
>>>>> On 12/30/2014 7:16 PM, wrote:
>>>>>> I've tried phase inversion, adding mild reverb and then using a
>>>>>> stereo expansion tool. Both provide some degree of a stereo effect,
>>>>>> though with phase inversion if you listen in mono - such as on a
>>>>>> mobile phone, the audio disappears.
>>>>>
>>>>> Sow's ear /= Silk purse
>>>>>
>>>>> The Orban stereo synthesizer did a pretty good job of fooling
>>>>> listeners
>>>>> in the early days of stereo broadcast. I wonder if there's an app for
>>>>> that. It works by dividing the source into frequency bands and
>>>>> throwing
>>>>> them left and right. It's more complex than bass on the left,
>>>>> treble on
>>>>> the right, and it's 100% mono compatible because it doesn't muck with
>>>>> the left/right phase.
>>>>>
>>>>>
>>>> A bunch of years ago I experimented with impulse functions that
>>>> would do just that. One can use Sound Forge's acoustic mirror
>>>> to create all sorts of impulse functions. Anyway, as I recall, I made
>>>> a long sweep and cut it up with the amplitude modulation function,
>>>> then created left and right impulses from that. Twas totally mono
>>>> compatible.
>>>>
>>>> Been a long time since I played with this stuff so the details of
>>>> exactly what I did are a bit fuzzy.
>>>>
>>>> ==
>>>> Later...
>>>> Ron Capik
>>>
>>>
>>> I wrote a program to compute the Hilbert transform* of a mono signal.
>>> Add delay and you get... something.
>>>
>>> *a fixed, 90-degree phase shift.
>>>
>>> You would not confuse the result with ambiance. It would sum to the 45
>>> degree shifted signal in mono.
>>>
>> OK, I wrote my own program, an extended version of acoustic mirror
>
>
> I thought Acoustic Mirror was just a fancy suite of impulses?

Dig a bit deeper and you'll find it also allows you to
roll your own impulses.

>
> Also, Google turned up this:
>
> http://www.theromneymarsh.net/history/mirrors.htm
>
> Wow. :)

Side note to that:
The large microwave horn that Penzias and Wilson used
to find the big bang was also one of those "acoustic
mirrors" in that it could easily pick up the sounds of kids
in a school playground ~15 miles away.

>
> < .....snip..... >
>
==
Later...
Ron Capik
--

[cporro]

i think it depends what you want from the stereo.

i'm going to give you an easy answer and it may be the most unrealistic of the suggestions above. what it does do is create a wide image. it's just a free plugin with a few controls. there is a slider with haas on one end and comb on the other, a delay and a mix parameter. you can dial is subtle to extreme in about 2 seconds. i think it's made my jesus sonic but there are probably tons of them. i'm kinda over most of the high end a high priced plugins these days.

chris

[Les Cargill[_4_]]

Ron C wrote:
> On 12/30/2014 10:33 PM, Les Cargill wrote:
>> Ron C wrote:
>>> On 12/30/2014 9:07 PM, Les Cargill wrote:
>>>> Ron C wrote:
>>>>> On 12/30/2014 3:30 PM, Mike Rivers wrote:
>>>>>> On 12/30/2014 7:16 PM, wrote:
>>>>>>> I've tried phase inversion, adding mild reverb and then using a
>>>>>>> stereo expansion tool. Both provide some degree of a stereo effect,
>>>>>>> though with phase inversion if you listen in mono - such as on a
>>>>>>> mobile phone, the audio disappears.
>>>>>>
>>>>>> Sow's ear /= Silk purse
>>>>>>
>>>>>> The Orban stereo synthesizer did a pretty good job of fooling
>>>>>> listeners
>>>>>> in the early days of stereo broadcast. I wonder if there's an app for
>>>>>> that. It works by dividing the source into frequency bands and
>>>>>> throwing
>>>>>> them left and right. It's more complex than bass on the left,
>>>>>> treble on
>>>>>> the right, and it's 100% mono compatible because it doesn't muck with
>>>>>> the left/right phase.
>>>>>>
>>>>>>
>>>>> A bunch of years ago I experimented with impulse functions that
>>>>> would do just that. One can use Sound Forge's acoustic mirror
>>>>> to create all sorts of impulse functions. Anyway, as I recall, I made
>>>>> a long sweep and cut it up with the amplitude modulation function,
>>>>> then created left and right impulses from that. Twas totally mono
>>>>> compatible.
>>>>>
>>>>> Been a long time since I played with this stuff so the details of
>>>>> exactly what I did are a bit fuzzy.
>>>>>
>>>>> ==
>>>>> Later...
>>>>> Ron Capik
>>>>
>>>>
>>>> I wrote a program to compute the Hilbert transform* of a mono signal.
>>>> Add delay and you get... something.
>>>>
>>>> *a fixed, 90-degree phase shift.
>>>>
>>>> You would not confuse the result with ambiance. It would sum to the 45
>>>> degree shifted signal in mono.
>>>>
>>> OK, I wrote my own program, an extended version of acoustic mirror
>>
>>
>> I thought Acoustic Mirror was just a fancy suite of impulses?
>
> Dig a bit deeper and you'll find it also allows you to
> roll your own impulses.
>

That would make sense. It would also have been easier than the way I did
it, but hey.... science!

>>
>> Also, Google turned up this:
>>
>> http://www.theromneymarsh.net/history/mirrors.htm
>>
>> Wow. :)
>
> Side note to that:
> The large microwave horn that Penzias and Wilson used
> to find the big bang was also one of those "acoustic
> mirrors" in that it could easily pick up the sounds of kids
> in a school playground ~15 miles away.
>

Sweet.

>>
>> < .....snip..... >
>>
> ==
> Later...
> Ron Capik

--
Les Cargill

[geoff]

On 31/12/2014 4:33 p.m., Les Cargill wrote:

>
>
> I thought Acoustic Mirror was just a fancy suite of impulses?
>


There is a convolution plug-in called Acoustic Mirror from Sony that
comes with, and has available extra, sets of impulses.

geoff

[Adrian Tuddenham[_2_]]

Ron C > wrote:

[...]
> The large microwave horn that Penzias and Wilson used
> to find the big bang was also one of those "acoustic
> mirrors" in that it could easily pick up the sounds of kids
> in a school playground ~15 miles away.

You don't need anything elaborate for that, have you ever heard the din
that kids can make?


--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

[Tim Sprout]

On 12/30/2014 9:16 AM, wrote:
> I've tried phase inversion, adding mild reverb and then using a stereo expansion tool. Both provide some degree of a stereo effect, though with phase inversion if you listen in mono - such as on a mobile phone, the audio disappears.
>
> Are there any hifalutin' tricks to creating a more authentic stereo field from a mono source that's also mono compatible?
>
> Thanks for all input.
>

Here's a link to a free VST plug-in to try.

Transforms a mono track into a stereo track using mid/side coding technique.

http://www.voxengo.com/product/stereotouch/


Tim Sprout

[Orlando Enrique Fiol]

In article >,
writes:
>There is a convolution plug-in called Acoustic Mirror from Sony that
>comes with, and has available extra, sets of impulses.

I have Sound Forge Pro 10 and have never been able to get Acoustic Mirror to
yield anything more than silence. Are the necessary impulse files stored in a
counterintuitive place? When I open the plugin, I don't "see" or hear any
useful presets with impulse names. This problem held true for me in previous
Sound Forge versions, so some fundamental aspect of this plugin's machination
is evading me. Can you or anyone else walk me through making Acoustic Mirror
useful, precisely for stereo simulation?
Thanks,
Orlando

[Orlando Enrique Fiol]

In article >,
writes:
>> There is a convolution plug-in called Acoustic Mirror from Sony that
>> comes with, and has available extra, sets of impulses.

I successfully downloaded all the available impulses, but don't see any
instructions for storing them. Looking through various plugin directories, I
don't see anything called Acoustic Mirror or Impulses. Where are they supposed
to reside?

[Ron C[_2_]]

On 12/31/2014 3:22 PM, Orlando Enrique Fiol wrote:
> In article >,
> writes:
>>> There is a convolution plug-in called Acoustic Mirror from Sony that
>>> comes with, and has available extra, sets of impulses.
>
> I successfully downloaded all the available impulses, but don't see any
> instructions for storing them. Looking through various plugin directories, I
> don't see anything called Acoustic Mirror or Impulses. Where are they supposed
> to reside?
>
You can put them any place you want. I have my impulses in
< E:\Audio Tool Box\_Impulse World\_Acoustic Mirror\ ... >
There's a pull down window labeled "Impulse: " and on the far
right a "Browse" button.
Browse to where ever you saved your impulse [ *.sfi ] files and
pick one.

Everything else should start falling into place from there.

==
Later...
Ron Capik
--

[Gray_Wolf]

On Wed, 31 Dec 2014 09:38:32 -0900, Tim Sprout >
wrote:

>On 12/30/2014 9:16 AM, wrote:
>> I've tried phase inversion, adding mild reverb and then using a stereo expansion tool. Both provide some degree of a stereo effect, though with phase inversion if you listen in mono - such as on a mobile phone, the audio disappears.
>>
>> Are there any hifalutin' tricks to creating a more authentic stereo field from a mono source that's also mono compatible?
>>
>> Thanks for all input.
>>
>
>Here's a link to a free VST plug-in to try.
>
>Transforms a mono track into a stereo track using mid/side coding technique.
>
>http://www.voxengo.com/product/stereotouch/
>
>
>Tim Sprout

I couldn't get Audition 3 & 6 to recognize it. Also Wavelab 6 or
Audacity.

md5: 43535aae0300405b044575b7fdf69b1e

[Orlando Enrique Fiol]

In article >,
writes:
>You can put them any place you want. I have my impulses in
>< E:\Audio Tool Box\_Impulse World\_Acoustic Mirror\ ... >
>There's a pull down window labeled "Impulse: " and on the far
>right a "Browse" button.
>Browse to where ever you saved your impulse [ *.sfi ] files and
>pick one.
>Everything else should start falling into place from there.

I'm not finding the pulldown or browse button when in the Acoustic Mirror
dialogue.
Orlando

[Tim Sprout]

On 12/31/2014 3:16 PM, Gray_Wolf wrote:
> On Wed, 31 Dec 2014 09:38:32 -0900, Tim Sprout >
> wrote:
>
>> On 12/30/2014 9:16 AM, wrote:
>>> I've tried phase inversion, adding mild reverb and then using a stereo expansion tool. Both provide some degree of a stereo effect, though with phase inversion if you listen in mono - such as on a mobile phone, the audio disappears.
>>>
>>> Are there any hifalutin' tricks to creating a more authentic stereo field from a mono source that's also mono compatible?
>>>
>>> Thanks for all input.
>>>
>>
>> Here's a link to a free VST plug-in to try.
>>
>> Transforms a mono track into a stereo track using mid/side coding technique.
>>
>> http://www.voxengo.com/product/stereotouch/
>>
>>
>> Tim Sprout
>
> I couldn't get Audition 3 & 6 to recognize it. Also Wavelab 6 or
> Audacity.
>
> md5: 43535aae0300405b044575b7fdf69b1e

Works for me in Audition CS6 by copying the Stereo Touch.dll file into

C:\Program Files (x86)\VSTPlugins, then scanning for it in Audition under:

Effects->Audio Plug-ins Manager. Is a VST plug-in (not VSTi or VST3).

Tim Sprout

[Ron C[_2_]]

On 12/31/2014 7:58 PM, Orlando Enrique Fiol wrote:
> In article >,
> writes:
>> You can put them any place you want. I have my impulses in
>> < E:\Audio Tool Box\_Impulse World\_Acoustic Mirror\ ... >
>> There's a pull down window labeled "Impulse: " and on the far
>> right a "Browse" button.
>> Browse to where ever you saved your impulse [ *.sfi ] files and
>> pick one.
>> Everything else should start falling into place from there.
>
> I'm not finding the pulldown or browse button when in the Acoustic Mirror
> dialogue.
> Orlando
>
I dropped a picture in my photobucket
<
http://s1351.photobucket.com/user/Editorial_Minstrel/media/Usenet/AcousticMirror_zpsae01cc2d.jpg.html
>

or, tiny_url
< http://tinyurl.com/l2kbmyp >

==
Later...
Ron Capik
--

[Gray_Wolf]

On Wed, 31 Dec 2014 15:59:11 -0900, Tim Sprout >
wrote:

>On 12/31/2014 3:16 PM, Gray_Wolf wrote:
>> On Wed, 31 Dec 2014 09:38:32 -0900, Tim Sprout >
>> wrote:
>>
>>> On 12/30/2014 9:16 AM, wrote:
>>>> I've tried phase inversion, adding mild reverb and then using a stereo expansion tool. Both provide some degree of a stereo effect, though with phase inversion if you listen in mono - such as on a mobile phone, the audio disappears.
>>>>
>>>> Are there any hifalutin' tricks to creating a more authentic stereo field from a mono source that's also mono compatible?
>>>>
>>>> Thanks for all input.
>>>>
>>>
>>> Here's a link to a free VST plug-in to try.
>>>
>>> Transforms a mono track into a stereo track using mid/side coding technique.
>>>
>>> http://www.voxengo.com/product/stereotouch/
>>>
>>>
>>> Tim Sprout
>>
>> I couldn't get Audition 3 & 6 to recognize it. Also Wavelab 6 or
>> Audacity.
>>
>> md5: 43535aae0300405b044575b7fdf69b1e
>
>Works for me in Audition CS6 by copying the Stereo Touch.dll file into
>
>C:\Program Files (x86)\VSTPlugins, then scanning for it in Audition under:
>
>Effects->Audio Plug-ins Manager. Is a VST plug-in (not VSTi or VST3).
>
>Tim Sprout

Thanks. It shows up in the drop-down menu under VST> RoomFx> Voxengo>
Stereo Touch.

[Peter Larsen[_3_]]

"Ron C" > skrev i en meddelelse
...

> I dropped a picture in my photobucket

That may not be helpful, Orlando is blind as I recall the world.

> Ron Capik

Kind regards

Peter Larsen

[Ron C[_2_]]

On 1/1/2015 9:44 AM, Peter Larsen wrote:
> "Ron C" > skrev i en meddelelse
> ...
>
>> I dropped a picture in my photobucket
>
> That may not be helpful, Orlando is blind as I recall the world.
>
>> Ron Capik
>
> Kind regards
>
> Peter Larsen
>
>
>

Big oops! I'd totally forgotten.
Thanks for the reminder Peter.

Now I'm not sure how to help beyond
this point.

Sorry for the miscommunication
Orlando. It seems like your user
interface is letting you down on
this one.

==
Later...
Ron Capik
--